Process of dehydrating heavy oils



F. VV. HARRIS. PROCESS 0F DEHYDRATING HEAVY OILS.

APPLICATION FILED MAY 3l. 1921.

Pafnte Mar. 28, 1922.

D STATES PATENT OFFICE.

FORD W. HARRIS, OF LOS ANGELES, CALIFORNIA, ASSIGNOR TO PETROLEUM RECTIFY- ING COMPANY, A CORPORATION OF CALIFORNIA.

l PROCESS OF DHYDRATING HEAVY OILS.

Specification of Letters Patent.

Patented Mar. 2-8, 1922.

Continuation of application Serial No. 271,332, led January 15, 1919. Renewed August 8, 1920, Serial No. 403,142. This application led May 31, 1921.

To all vwhom it mary concern:

Be it known that I, FORD lV. HARRIS, a citizen of the United States, residing at Los Angeles, in the county of Los Angeles and State of California, have invented a new and useful Process of Dehydrating Heavy Oils, of which the following is a specification.

My invention relates to the art of dehydratmg petroleum oils, and more particularly to the art of dehydrating oils which are very viscous and heavy. There have been developed and are now in commercial use various types of electrical dehydrators in which the minute water particles of petroleum emulsions are agglomerated into larger drops which are then settled out by gravity. This settlement may take place in the dehydrator itself, or it may take place in auxiliary tanks provided for that purpose. It has been found in the operation of such dehydrators that where very heavy tars or oils are operated on, that it is possible to agglomerate the emulsified water into relatively large particles, but that in many cases it is almost impossible to cause the water to settle even after it has been agglomerated.

It is the purpose of my invention to provide a process by which such heavy oils may be treated.

Further objects and advantages will be made evident hereinafter.

Referring to the drawings, which are for illustrative purposes only,

Fig. l is a diagram showing the apparatus required to carry on the process, a portion of this apparatus being shown in section to better illustrate the invention.

Fig. 2 is a liuid flow diagram illustrating the operation of the process.

The apparatus employed comprises a still 11, a dehydrator 12, a mixer 13, a. pump 14 and a heat interchanger 15. The still 11 may be of any preferred form, that shown being set in a conventional set-ting 20 and having a gas or oil burner 21 projecting into the fire box 22. The still 11 is provided with a vapor Outlet pipe 23, a residuum outlet pipe 24 and an inlet pipe 25 which is provided with a valve 26.

The dehydrator 12 may be of the form shown in my copending application, Serial No. 261,728, or it may be of any other con- Serial No. 473.874.

venient form. That lshown consists of a tank 3() in which are suspended two series of electrodes 31 and 32, the electrodes 31 being supported on insulators 33 connected to some source of electrical potential, not shown, through an outlet bushing 34. A steam coll 35 is provided in the bottom of the dehydrator and a water outlet pipe 36 controlled by a valve 37 is provided near the bottom thereof. A perforated oil inletpipe admits oil to the dehydrator, the hot dry 01.1 belng taken off the top through the pipe 25.

The mixer 13 consists of a shell 40 in which are placed series of nested cones 41. O11 vapor is forced through these y cones from the pump 14 vthrough a pipe 42, oil belng supplied outside the cones through a pipe 43. The mixer is connected through a pipe 44 and a valve 45 with the pipe 38.

The pump 14 may be of any convenient form. The suction side of the pump is connected to the vapor outlet pipe 23 of the still 11, the pressure side of the pump being connected t0 the pipe 42.

The heat interchanger 15 consists of a tight shell 50 having intermediate heads 51 between which tubes 52 are placed. Oil is admitted to the space around the tubes, through the residuum outlet pipe 24 which connects into the shell 50, this oil being withdrawn through a pipe 54. The oil to be treated is admitted to the space inside the tubes through an inlet pipe 55, being withdrawn through the pipe 43.

The method of operation of the invention is as follows:

The oil enters the heat interchanger 15 through the pipe and passes through the tubes 52 in which it is heated by hot oil which is delivered through the pipe 24, the heated oil passing through the pipe 43 into the space inside the shell 40 and around the cones 41. Vapor is forced by the pump 14 through the pipe 42 and through the center of the cones 41 mixing therein with the oil delivered by the pipe 43 and thoroughly heating the same something after the manner of a jet condenser. The vapor delivered by the pipe 42 may be gasoline vapor or it may preferably be a vapor ofthe lower boiling distillate.

The mixing of such vapors with the heavy crude oil tends to reduce its viscosity and to its viscosity.

If the original oil supplied through the pipe 55 were to pass into the dehydrator 30 the necessary without modification, the action of the electrodes 31 and 32 on this oil would tend to break the emulsion and to agglomerate the small Water globules contained therein into larger masses. The agglomerated water globules would tend to settle in the dehydrator but would settle so very slowly in the heavy oil that the capacity of the apparatus would be quite small. With the lighter and less viscous mixture delivered through the pipe 44 the same dehydrating action takes place in that the water globules are agglomerated into larger masses, but at the same time the mixture is sufficiently liuid to allow the water masses to fall readily therethrough into the bottom of the dehydrator 3() and to be withdrawn through the pipe 36.

The hot dry oil is taken off from the top of the dehydrator through the pipe 25 and passes into the still 11. The induction of the vapors in the mixer 15 heats the oil to a considerable degree, say to 150 degrees Fahrenheit but to a degree below the boiling point of the distillates used. In the still 11 the mixture of oil and distillate is raised sufficiently to cause the distillate to pass off as a vapor through the pipe 23, passing back through the pump 14 into the mixer 13. rlhe heavy oil passes through the pipe 24 into the heat interchanger 15 thereby warming the entering oil, this being a simple and economical means for the conservation of heat.

Some oils contain sufficient oil vapors to supply the necessary distillates for the operation of the process.` It is generally advisable, however, to charge the apparatus with proportion of distillate to start, that is to say, if the dehydrator has a cubical content of say 150 barrels of oil about iift barrels of distillate are placed in the de ydrator before the operation is started. This fifty barrels of distillate is' kept in circulation around the closed ring, being put into the oil in the mixer 13, continuing in it through the dehydrator 12, and

being removed from the oil in the still 1l and passed back to the mixer 13. Almost all oils have suiicient light fractions to maintain the supply of distillates, but in some cases it may be necessary from time to time to add small'amounts of distillates which may conveniently be done at any point in the system, as for example, through the pipe 10() controlled by the valve 101.

It will be seen that my invention comprises the conception of a circulating ring of distillate which is associated with the heavy oil during its passage through the dehydrator, for the purpose of expediting the settling action therein.

This application is a continuation of Serial No. 271,332 filed January 15, 1919 which was renewed as Serial No. 403,142 on Aug. 8, 1920.

What I claim is: l

1. Any method of dehydrating heavy oils which comprises mixing light distillates with the oil to render it less viscous; subjecting the mixture to dehydrating action to remove the water; subjecting the mixture to sufliciently high temperature to distill oli" said light distillates; and utilizing the distillate so distilled off for the dilution of additional heavy oil.

2. Any method of dehydrating heavy oils which comprisesmixing light distillates With the oil to render'itiless viscous; subjecting the mixture to dehydrating action to remove the water; subjecting the mixture to suiiciently high temperature to distill off said light distillates; and injecting the distillate vapors so produced into said heavy oil for the purpose of diluting and heating it.

3. An apparatus for dehydrating heavy oils comprising a dehydrator; a still; means for heating said still; means for passing fluid from said dehydrator into said still; and means for mixing the 'vapors from said still with the oil to be dehydrated before it enters said dehydrator.

4. A method of dehydrating heavy oils which comprises mixing said heavy oils with a solvent which renders the oilsI less viscous and reduces their specific gravity; treating said mixture to remove the Water therefrom; and thereafter treating the dehydrated mixture to 'remove the solvent therefrom.

In testimony whereof, I have hereunto set my hand at Los Angeles, California, this 26th day of May, 1921.

FORD W. HARRIS. 

